Mend Heating, Home Heating Systems

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Home Heating Systems

Mend Mend Heating, Home Heating Systems

How do I rectify aU9 Code?

Worcester Bosch Greenstar 37CDi Combi showing code U9?
My boiler is showing code U9, I know this means that the temp has risen to 99 degrees. The result when I turn the hot tap on the boiler just stops and we have no hot water. What causes this and what can I do to mend it? Do I need an engineer?

March 2022

It might be a failed pump. Safest is to get a Gas Safe certified engineer to look at it.

I think Worcester Bosch will offer a maintenance contract. You'll probably have to buy a 6 month subscription but it might be worthwhile long term.

March 2022


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